Marine Snow

Assembled from 24 blocks · 2 evidence · 21 related

1. Story
2. The continuous downward rain of organic particles - dead plankton, faecal pellets, mucus aggregates, phytodetritus - that carries surface-produced carbon into the deep ocean. It is the food supply for almost everything below the photic zone and the mechanical core of the biological carbon pump. Most of it is consumed or remineralised on the way down: published estimates put the fraction of surface primary production reaching the abyssal seafloor at only a few percent, and recent work indicates sinking particles can lose roughly half their carbon and around 60 percent of their nitrogen during descent, feeding free-living microbes en route. A process, not a place.
3. Knowledge
4. Epipelagic Zone (Sunlight Zone)
5. Bathypelagic Zone (Midnight Zone)
6. Abyssopelagic Zone (Abyssal Zone)
7. Marine Snow
8. Connections
9. Abyssopelagic Zone (Abyssal Zone)
10. Bathypelagic Zone (Midnight Zone)
11. Epipelagic Zone (Sunlight Zone)
12. Bathypelagic Zone (Midnight Zone)
13. Hadal Zone
14. Mariana Trench
15. Marine Snow
16. Mesopelagic Zone (Twilight Zone)
17. Abyssopelagic Zone (Abyssal Zone)
18. Marine Snow
19. Giant Tube Worm (Riftia pachyptila)
20. Mesopelagic Zone (Twilight Zone)
21. Marine Snow
22. Evidence
23. Sediment-trap measurements indicate that only a small percentage of surface primary production reaches the deep seafloor - of the order of 3-4 percent in the subarctic Pacific - and that around 99 percent of the organic carbon arriving is consumed rather than buried.
24. Below the photic zone the ecosystem depends on sinking organic material (marine snow) and on food falls; bioluminescence is the dominant light source, and deep pelagic predators such as anglerfishes use luminous lures in a food-scarce environment.